1. Field of the Invention
The present invention relates to a terminal for a connector with an engagement mechanism.
2. Prior art
To firmly hold a terminal in a connector, the following process has been hitherto generally employed. Specifically, an engagement piece formed by cutting and bending a part of the terminal in the upward direction is engaged with the bottom wall of a terminal receiving chamber in an electrical insulative housing of the connector. Otherwise, an engaging arm formed integral with a ceiling wall of the terminal receiving chamber is engaged with a shoulder portion or a hole formed on an electrical connecting portion of the terminal.
However, each of the engagement piece and the engagement arm is designed with small dimensions, and as a female connector is repeatedly connected to and disconnected from a male connector, they are readily damaged or broken. In addition, there arises a malfunction that the terminal is disconnected from the opponent housing or incorrect contact occurs therebetween.
In the circumstances as mentioned above, a proposal has been made with respect to a connector as shown in FIG. 7 and FIG. 8 wherein the connector designated by reference character K is constructed such that through holes 3 are formed through an electrical insulative housing 2 and an insert pin 4 is fitted into the through holes 3 so that engagement projections 5 formed on side wall surfaces of the insert pin 4 are brought into contact with engagement portions 6 projecting from an electrical contact portion la of a terminal 1 to establish double engagement therebetween in addition to the disconnection preventing means as mentioned above (cf. Japanese Unexamined Patent Publication NO. 64-54678).
The insert pin 4 to be inserted into the connector K is molded of an electrically insulative synthetic resin in the same manner as the electrical insulative housing 2, while the terminal 1 is made of a sheet of metallic material having electrical conductivity and the engagement portions 6 are formed by cutting and bending a part of the sheet of metallic material for the terminal 1 in the upward direction. With this construction, any trouble does not arise as long as the terminal 1 is exactly inserted into the housing 2 at a predetermined position when the insert pin 4 is fitted into the through holes 3 for bringing the engagement portions 6 of the terminal 1 in engagement with the engagement projections 5 of the insert pin 4. However, in case that the terminal 1 is incompletely inserted into the housing 2 of the connector K, there arise problems as illustrated in FIG. 9 and FIG. 10.
Specifically, in case that the position where the terminal 1 is inserted into the housing of the connector K is largely dislocated away from a predetermined position as shown in FIG. 9, the engagement projections 5 of the insert pin 4 come in contact with the uppermost ends 6a of the engagement portions 6, resulting in the insert pin 4 failing to be inserted to reach a predetermined position. This means that the incomplete insertion of the terminal into the housing of the connector K can visually be recognized with operators's eyes.
On the other hand, in case that the position where the terminal 1 is inserted into the housing of the connector K is slightly dislocated away from the predetermined position as shown in FIG. 10, the engagement projections 5 of the insert pin 4 come in contact with shoulder portions 6b of the engagement portions 6 of the terminal 1. Since the shoulder portions 6b of the engagement portions 6 are formed with sharp edges by cutting and bending a sheet of metallic material having a small thickness in the upward direction, there arises an occasion that the insert pin 4 is inserted to the predetermined position because a part of each of the engagement projections 5 of the insert pin 4 is cut off with the foregoing sharp edges of the shoulder portions 6b when the insert pin 4 is thrusted with an operator's hand as shown in FIG. 11. This means that the incomplete insertion of the terminal 1 into housing of the connector K can not visually recognized with operator's eyes. In this case, there arises a problem that terminals are incompletely connected to each other, causing incorrect electrical conduction to occur with the connector K.